Electric valve grinder



Mar. 27, 1923, 1,449;908

- J. J. MC GUCKIN ET AL ELECTRIC VALVE GRINDER Filed Apr.2 1921 Patented Mar. 27, 1923.

UNITED STATES PATENT OFFICE.

JOHN J'. MCGUCKIN AN D JOHN PEYER, OF BROOKLYN, YORK, ASSIGNORS TO LOUIS SCHWAB, DOING BUSINESS UNDER BUSINESS NAME OR STYLE OF STEVENS Q:

COMPANY OF NEW YORK, N. Y.

ELECTRIC VALVE GR'INDER.

Application filed April 2,

T o a]! 'u'homv it may concem Beit known that we, JOHN J. MCG-UCKIN and JOHN PEYER, being both citizens of the United States, and residents of the borough of Brooklyn, city and State of New York,

have invented certain new and useful Improvements in Electric Valve Grinders, of

which the followi'n is a specification.

Our invention rel tes to tools which are adapted to actuate the valves of internal combustion engines and the like, in their seats so as to get rid of the products and results of combustion and to cause them to wear or grind, as it is called, tight joints with their seats. And our improvements are directed particularly to means whereby the tool shall .be automatically set in motion when it is applied in working position, and shall, also, be automaticall stopped when excessive pressure is applied to it or when it is disconnected from the valve head.

As is well understood in the art, it is necessary toapply such a tool in gripping relation to the valve head before its actuating element begins to move. And when so applied, it is desirable that it shall start to operate with as little delay as possible, and also without the manipulation of complicated starting mechanism. by the operator.

It is also of the first importance that excessive premure shall not be applied to the valve head during the grinding operation, as that is likely to produce grooves in the valve head or seat which will cause a leaky joint. And it is our aim to obtain these results, in the manner which we will now proceed to explain.

In the drawings, Fig. 1 is an elevation of a tool embodying our improvements; Fig. 2 is a top view of the same; Fig. 3 is a vertical sectional view of the same; Fig. 4 is a cross sectional view taken on the line 4-4 of Fig. 3 looking down; Fig. 5'is a detail of the switch taken as looking to the" right on Fig. 3, parts being omitted for clearness; and Fig. 6 is a diagrammatic sketch of the electric circuit.

Similar parts are designated by similar reference numerals in all the figures.

A casing 1 is provided with a conventional armature shaft 2, armature 3 and field magnets 4, 4, indicated in broken lines in Fig. 3; and suitable top and bottom casings 5, 6 are, secured, as by screws 7, 7, and

1921. Serial No. 457,864.

8, 8, to the motor casing. The lower end of the armature shaft 2 is provided with a pinion 9, which meshes with a gear 10, pivoted at ll-below the bottom of the motor casing 1. And this gear 10 carries a wrist pin 12 which extends down through a slot 13 in an arm 14 carried by the upper end of the shank 15 which passes through the bushing 16 in the neck 17 of the casing 6. The arm 14 can slide up and down on the wrist pin.

Below the end of the bushing 16 is a coiled spring 18, which is held in place by suitable means, such as washers 19, 19 above a collar 20, secured to the shank by set screws 21, 21, or other suitable means. And to the end of the shank is attached a suitable element, as 22, for grasping a valve head.

The bushing 16 is provided with a groove 23, in which slides a rod 24 the lower end. of which rests against the collar 20, while its upper end extends up through the motor casing 1 and rests below one end of a switch lever 25, pivoted in a suitable bearing 26 on top of the motor casing, and normally tilted up,as shown in Fig. 3, by the action of a spring 27 extended between the lever and the motor casing.

Below the free end of the lever 25"is a switch contact 28, which is preferabl formed of a spring loop having a contracte switch engaging portion 29,- and being exanded above and below that portion; so that if the end of the lever 25 is depressed so as to pass between the points 29, 29 it will contact therewith so as to close a cir-. cuit, which, however, will be broken if the end of the lever is moved substantially above or below that point.

Suitable cont-acts 30, 31 are mounted in the upper end of the casing 5; and from 30 a conductor 32 extends down to the switch contact 28, the circuit passing thence through the switch lever 25, and its bearing 26 through line 33, to the motor and thence by line 34 to contact 31.

The parts of the tool are preferably so adjusted that when the tool is rested upon its end, 22, the weight of the tool will be sufficient to so far overcome the resistance of the springs 18 and 27 so as to allow the shank 15 to slide up in/its bushing sufliciently forthe rod 2 1 to tilt the switch lever 25 until it closes with contact 28, closing the electric circuit and starting the motor, which, throughthe gears 9, 10, wrist pin 12, and arm 14 will oscillate the shank 15 as the motor revolves.

If, howeverysubstantial pressure 1s applied to 'the tool, the springs 18, 27 w ll yield sufiiciently to allow the rod 24 to tilt the switch lever 25 so that its free end will pass down into theopen loop of the contact 28, thereby breaking the electric circuit and stopping the motor' 3. And, conversely, while the motor is running, if the tool be raised so as to relieve the pressure on its shank, the springs will cause the switch to open, breaking the circuit and stopping the motor. By these means we secure a tool which is siinple,,efficient and compact, which automatically starts itself when placed in proper operative position, and also automatically stops itself when raised from duty or when unduly pressed to duty, and which is so far self-contained that it is not easily injured in ordinary work.

It will be understood that details of combinations may be modified, by the use of mechanical equivalents or the like, without departing from the spirit of our invention or the scope of the claims.

Having thus described our invention what we claim and desire to secure by Letters Patent of the United States is 1. The combination, in a valve grinding tool embodying a casing, an electric motor therein, electrical conductors, and a slidable,

valve-engaging shank rotatable by the mo tor, of an electric switch, and means, operable, by a limited longitudinal movementof the shank, to close the switch, and, by a continuation of such movement, to open the switch.

2. The combination, in a valve grinding tool embodying a casing, an electric motor therein, electrical conductors, and a slidable, valve-engaging shank rotatable by the motor, of an electric switch, and means, operable, by a limited longitudinal movement of the shank, produced by the normal weight of the tool when resting on the shank, to close the switch, and, by a continuation of such movement, to open the switch.

3. The combination, in a valve grinding tool embodying a casing, an electric motor therein, electrical conductors, and a slidable valve-engaging shank rotatable by the 'motor, of an electric switch, and means, operable, by a limited longitudinal movement of the shank, to close the switch, and, by a continuation or reversal of such movement, to open the switch.

4. The combination, in a valve grinding tool embodying a casing, an electric motor therein, electrical'conductors, and a slidable, valve-engaging shank rotatable by the motor, of an electric switch, and means, operable, by a' limited longitudinal movement of the shank, produced by the normal weight of the tool when resting on the shank, to close the switch.

5. The combination, in a valve grinding tool embodying a casing, an electric motor therein, electrical conductors, and a slidable,

valve-engaging shank rotatable by the moswitch, and to again close and then open the i switch by a reverse longitudinal movement of the shank.

J OHN J. MGGUCKIN. JOHN PEYER. 

